H2O self-broadening coefficients of rotation-vibration lines in the 15 500-16 000 cm-1 region

Line broadening coefficients of the Н2О-Н2О system were investigated in the region 15500 – 16000 cm-1 using a high resolution Fourier-transform spectrometer IFS-125M. The White type multipass absorption cell with a basic length of 60 cm was used. Least-square-fitting algorithm WXSPE was used to retrieve of the spectroscopic parameters from measured spectral data set. Calculations of self-broadening are performed using a semi-empirical approach. This method is further developed by using anharmonic wavefunctions in the estimates of line profiles. This approach explicitly takes into account all scattering channels induced by collisions. Calculated data are in a good agreement with the measured ones. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Verification of H2O lines from the HITRAN database for remote sensing of the water vapour isotopic composition

The quality of the spectroscopic line parameters from the HITRAN Database for remote sensing of the water vapour isotopic composition of the atmosphere is widely discussed. In this research we show that the HITRAN-2008 data for H2O isotopologues in the near infrared spectral range (4000-6400 cm-1) is reasonably good. The HITRAN data was tested with independent calculation (ab initio et al.). For the evaluation we've used two following criteria: a quality of the fitting of atmospheric spectra measured at the Ural Atmospheric Station (UAS, Kourovka) with the high-resolution Fourier-transform infrared spectrometer and an agreement between the retrieved HDO/H2O relative concentration ratios in the atmospheric column and the results of the simulation of the isotopic general circulation model ECHAM5-wiso (validated for Kourovka region). © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Line broadening of SO2 and CO2 volcanic activity gases in the Earth’s atmosphere

Calculations of the CO2-broadening coefficients of sulfur oxide lines by the semi-empirical method [Mol. Phys. 102 (2004) 1653] and averaged energy difference method [Atmosph. Ocean. Optics 28 (2015) 403] are presented. In this work, 41 lines are considered, the rotational quantum number J varies from 14 to 51. Calculations of the line widths are carried out for room temperature (296 K), and also for the temperature range typical for the Ears atmosphere. There is good agreement with the literature data. The carbon dioxide lines broadening coefficients induced by nitrogen, nitrogen oxide, carbon monoxide and carbon dioxide at room temperature (T = 296 K) are obtained for a wide range of the rotational quantum number J (up to 100). The temperature exponents are calculated for every line widths. The calculations were performed by a semi-empirical method, based on the semiclassical impact theory of line broadening and modified by introducing additional correction factor whose parameters can be determined by fitting the broadening or shifting coefficients to the experimental data

Linewidths and temperature exponents of CH3CN-N2

Calculations of nitrogen-broadening coefficients and their temperature exponents for methyl cyanide lines at the room temperature using semi-empirical method are presented. They were performed for wide ranges of rotational quantum numbers J and K requested for atmospheric applications: J from 0 till 70 and K from 0 till 20. The temperature exponents were calculated for every mentioned line. Extensive line lists are provided for the Earth and Titan atmosphere temperature ranges. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

N2-broadening coefficients of CH3CN rovibrational lines and their temperature dependence for the Earth and Titan atmospheres

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CH3CN self-broadening coefficients and their temperature dependences for the Earth and Titan atmospheres

Theoretical self-broadening coefficients and associated temperature dependences for methyl cyanide lines in parallel (ΔK = 0) bands are reported for large ranges of rotational quantum numbers (0 ⩽ J ⩽ 70, K ⩽ 20) requested by spectroscopic databases. The calculations are performed by a semi-empirical method, particularly suitable for active molecules with large dipole moments, which needs only a few experimental data for model parameters fitting. Since the common power law for the temperature-dependence exponents is invalid for wide temperature ranges, two separate sets of temperature exponents are provided for Earth and Titan atmospheres applications